In a digital communication network, data (e.g., one or more bits) is communicated between network devices using radios and network links (e.g., channels). Each link represents a physical and/or logical communication path between two or more devices and each radio transmits and/or receives data transmitted between network devices over these links. A transmitting radio is responsible for encoding data into a radio signal (e.g., by modulating one or more subcarrier signals), and transmitting the modulated subcarrier signals over a link. A receiving radio receives the transmitted signal and decodes the signal into digital data.
Network links can be established from both wired and wireless media and some network links are more susceptible to signal degradation than others. Signal degradation, such as fading, can impact whether a receiving radio correctly decodes an intended data unit transmitted on the network. Interference and signal loss can cause a radio signal to fade and/or introduce noise into the signal. Faded and noisy signals, once decoded, can lead to inaccurate and/or corrupted data. Signals that travel in the same physical link may operate at different frequencies such that a single link may include multiple channels of communication.
Some networks utilize signal modulation and mixing techniques to improve the bandwidth and rate of a radio signal transmission and communication links. For instance, rather than serially sending or receiving individual units of data with individual signals during individual blocks of time, modulation allows a radio to send and receive multiple units of data simultaneously and in parallel by combining multiple signals that each represent individual data units into one modulated signal that is transmitted at one moment in time. The recipient of a modulated signal can receive multiple data units simultaneously by de-modulating the modulated signal into multiple individual signals that each represent single units of data.